v2.4.0.6

DERIVATIVES AND RISK MANAGEMENT ACTIVITIES Narrative (Details) (USD $) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2012 | Mar. 31, 2011 | Dec. 31, 2011
Derivative [Line Items] |  |  |
New interest rate swaps, notional amount | $ 200,000,000 |  |
New interest rate swaps, hedged debt instruments | 4.75% senior notes |  |
New interest rate swaps, interest rate received | 4.75% |  |
New interest rate swaps, pay rate | variable rate based on one month USD LIBOR plus a percentage that varies with each agreement |  |
Notional amount of fixed-to-floating interest rate swaps | 470,000,000 |  | 270,000,000
Weighted-average interest rate paid, fixed-to-floating interest rate swaps | 2.90% |  |
Terminated interest rate swaps, notional amount | 225,000,000 |  |
Proceeds from (payments for) termination of interest rate swaps | (25,358,000) | 0 |
Notional amount of forward-starting interest rate swaps | 275,000,000 |  | 500,000,000
Volume of commodity contracts (in barrels) | 42,300,000 |  | 27,800,000
Margin Deposit | 6,600,000 |  | 1,100,000
Gain (loss) to be reclassified during next 12 months, commodity contracts | (24,300,000) |  |
Gain (loss) to be reclassified during next 12 months, forward-starting interest rate swaps | $ (2,500,000) |  |
Maximum length of time hedged, commodity contracts | three years |  |
Maximum length of time hedged, forward-starting interest rate swaps | one year |  |

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- Definition The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 45 -Subparagraph b(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6887037&loc=d3e80748-113994 + Details
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- Definition Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 45 -Subparagraph b(3) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6887037&loc=d3e80748-113994 + Details
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- Definition Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 45 -Subparagraph b(3) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6887037&loc=d3e80748-113994 + Details
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